Mobile X-ray apparatus

CROSS-REFERENCE TO RELATED APPLICATION

0001This is a continuation application of U.S. patent application Ser. No. 15/471,657, filed Mar. 28, 2017, in the U.S. Patent and Trademark Office, which claims priority from Korean Patent Application No. 10-2017-0004164, filed Jan. 11, 2017, in the Korean Intellectual Property Office. The disclosure of the above-named application is incorporated herein by reference in its entirety.

BACKGROUND

1. Field

0002The present disclosure relates to X-ray apparatuses including lithium ion batteries.

2. Description of the Related Art

0003X-rays are electromagnetic waves having wavelengths of 0.01 to 100 angstroms (Å), and are widely used, due to their ability to penetrate objects, in medical apparatuses for imaging the inside of a living body or in non-destructive testing equipment for industrial use.

0004An X-ray apparatus using X-rays may obtain X-ray images of an object by transmitting X-rays emitted from an X-ray source through an object and detecting a difference in intensities of the transmitted X-rays via an X-ray detector. The X-ray images may be used to examine an internal structure of an object and diagnose a disease of the object. The X-ray apparatus facilitates observation of an internal structure of an object by using a principle in which penetrating power of an X-ray varies depending on the density of the object and atomic numbers of atoms constituting the object. As a wavelength of an X-ray decreases, penetrating power of the X-ray increases and an image on a screen becomes brighter.

0005Since an X-ray radiation device and an X-ray detector of the X-ray apparatus are generally affixed to a specific space, a patient needs to be transferred to an examination room where the X-ray apparatus is located for X-ray imaging.

0006However, it is difficult to use a general X-ray apparatus in the case of performing X-ray imaging examinations on patients with mobility problems. Thus, a mobile X-ray apparatus has been developed to perform X-ray imaging without space limitations.

0007In the mobile X-ray apparatus, an X-ray radiation device is mounted on a movable main body, and a portable X-ray detector is used. Due to this configuration, the mobile X-ray apparatus may be taken directly to a patient with reduced mobility in order to perform X-ray imaging.

0008Lead-acid batteries are generally inexpensive and are widely used in mobile X-ray apparatuses.

0009However, lead-acid batteries have a short life span (two years or 500 cycles), are bulky and heavy, and may release hazardous materials into the environment.

0010Furthermore, use of such bulky or heavy lead-acid batteries is inconvenient when trying to move an X-ray apparatus.

SUMMARY

0011Provided are mobile X-ray apparatuses including lithium ion batteries that have a relatively long life span, are small and lightweight, and are environmentally-friendly as they do not release hazardous materials, compared to lead-acid batteries.

0012Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments.

0013According to an aspect of an embodiment, a mobile X-ray apparatus includes: an X-ray radiation device; a controller configured to control the X-ray radiation device; a power supply configured to supply operating power to the X-ray radiation device and the controller via a lithium ion battery and control overcurrent occurring during X-ray emission by the X-ray radiation device; and a charger configured to charge the power supply, wherein the controller, the power supply, and the charger are each constituted by a physically separate module, and the power supply and the charger are each encased in a metal case.

0014The power supply may include: the lithium ion battery; a battery management system (BMS) circuit configured to detect a state of the lithium ion battery and control an operation of the power supply; a discharge field effect transistor (FET) configured to control the overcurrent and including a plurality of FETs connected in parallel; and a charge FET.

0015The discharge FET and the charge FET are further configured to control a path of a discharge current or a charge current when the lithium ion battery is discharged or charged.

0016The BMS circuit is further configured to control an operation of a protection circuit protecting against at least one of over-discharge, overcurrent, overheating, and unbalancing between cells in the lithium ion battery.

0017The power supply may further include a first current sensor and a second current sensor, and the BMS circuit is further configured to detect, during the X-ray emission by the X-ray radiation device, the overcurrent by activating the second current sensor.

0018The mobile X-ray apparatus may further include a current sensor located at an output terminal of the charger in order to detect a charge current.

0019The controller, the power supply, and the charger may respectively include communication connectors, and the controller, the power supply, and the charger are configured to communicate with one another via the communication connectors according to a controller area network (CAN) protocol.

0020The power supply may include a temperature sensor configured to detect a temperature of the lithium ion battery, and the controller is further configured to directly monitor information about the temperature detected by the temperature sensor.

0021The power supply and the charger may respectively include interrupt pins that can be directly controlled by the controller, and the controller is further configured to respectively turn off the power supply and the charger via the interrupt pins.

0022The power supply is further configured to receive data necessary to update firmware for the BMS circuit from the controller via the communication connector.

0023The power supply is further configured to receive, when the power supply is connected to the controller via the communication connector, data necessary to update firmware for the BMS circuit, from the controller.

0024The BMS circuit may include a master BMS circuit and a plurality of slave BMS circuits, and each of the slave BMS circuits may be directly connected to the lithium ion battery to detect information about the state of the lithium ion battery and transmit the detected information to the master BMS circuit via a communication interface.

0025The lithium ion battery may include a plurality of cell groups, each cell group having a plurality of lithium ion battery cells connected in parallel.

0026A battery pack may be formed by connecting the plurality of cell groups of the lithium ion battery in series, and the battery pack may be connected to each of the slave BMS circuits.

0027The lithium ion battery may include four lithium ion battery cells that are connected in parallel to form a cell group.

0028The metal case of the power supply may include at least one handle.

0029A weight of the power supply may be less than or equal to 35 kilograms (kg).

0030A partition wall may be provided between the lithium ion battery and the BMS circuit.

0031Each cell in the lithium ion battery may be inserted into a holder made of a flame retardant material.

0032The mobile X-ray apparatus may further include a frame that is attached to a main body of the mobile X-ray apparatus via a hinge so as to be capable of pivoting around a hinge axis, and a system board may be mounted on the frame.

BRIEF DESCRIPTION OF THE DRAWINGS

0033These and/or other aspects will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings in which:

0034<figref idref="DRAWINGS">FIG. 1</figref> illustrates an X-ray apparatus implemented as a mobile X-ray apparatus, according to an embodiment;

0035<figref idref="DRAWINGS">FIG. 2</figref> illustrates an X-ray detector included in the X-ray apparatus of <figref idref="DRAWINGS">FIG. 1</figref>;

0036<figref idref="DRAWINGS">FIG. 3</figref> is a block diagram of an X-ray apparatus according to an embodiment;

0037<figref idref="DRAWINGS">FIG. 4</figref> illustrates components of a power supply included in a mobile X-ray apparatus, according to an embodiment;

0038<figref idref="DRAWINGS">FIG. 5</figref> is a schematic diagram illustrating discharging of a lithium ion battery according to an embodiment;

0039<figref idref="DRAWINGS">FIG. 6</figref> is a schematic diagram illustrating charging of a lithium ion battery according to an embodiment;

0040<figref idref="DRAWINGS">FIG. 7</figref> is a detailed block diagram of a mobile X-ray apparatus according to an embodiment;

0041<figref idref="DRAWINGS">FIG. 8</figref> illustrates a shutdown process performed by a mobile X-ray apparatus according to an embodiment;

0042<figref idref="DRAWINGS">FIG. 9</figref> illustrates a charger according to an exemplary embodiment;

0043<figref idref="DRAWINGS">FIG. 10</figref> is a timing diagram of an operation of charging a lithium ion battery according to an exemplary embodiment; and

0044<figref idref="DRAWINGS">FIG. 11</figref> is a flowchart of a method of sensing of a low current state by a charger, according to an exemplary embodiment.

0045<figref idref="DRAWINGS">FIG. 12</figref> illustrates an X-ray apparatus according to an embodiment;

0046<figref idref="DRAWINGS">FIG. 13</figref> illustrates an X-ray apparatus, according to an embodiment;

0047<figref idref="DRAWINGS">FIG. 14</figref> illustrates a state in which a power supply is detached from an X-ray apparatus, according to an embodiment;

0048<figref idref="DRAWINGS">FIG. 15</figref> illustrates an X-ray apparatus according to an embodiment;

0049<figref idref="DRAWINGS">FIG. 16</figref> illustrates a power supply according to an embodiment;

0050<figref idref="DRAWINGS">FIG. 17</figref> is an example of a controller according to an embodiment;

0051<figref idref="DRAWINGS">FIG. 18</figref> illustrates a charger according to an embodiment;

0052<figref idref="DRAWINGS">FIG. 19</figref> illustrates a state in which a power supply, a controller, and a charger are connected to one another, according to an embodiment;

0053<figref idref="DRAWINGS">FIG. 20</figref> illustrates a power supply according to an embodiment;

0054<figref idref="DRAWINGS">FIG. 21</figref> is a cross-sectional view of a power supply according to an embodiment;

0055<figref idref="DRAWINGS">FIG. 22</figref> is a block diagram of a configuration of a battery management system (BMS) circuit according to an embodiment;

0056<figref idref="DRAWINGS">FIG. 23</figref> shows a state in which a battery pack is mounted in a power supply according to an embodiment;

0057<figref idref="DRAWINGS">FIG. 24</figref> illustrates a structure of a battery pack according to an embodiment;

0058<figref idref="DRAWINGS">FIG. 25</figref> illustrates a configuration of a slave BMS circuit according to an embodiment;

0059<figref idref="DRAWINGS">FIG. 26</figref> illustrates a structure in which a system board is mounted on a side of an X-ray apparatus, according to an embodiment; and

0060<figref idref="DRAWINGS">FIG. 27</figref> illustrates a state in which frames of <figref idref="DRAWINGS">FIG. 26</figref> are open.

DETAILED DESCRIPTION

0061The present specification describes principles of the present disclosure and sets forth embodiments thereof to clarify the scope of the present disclosure and to allow those of ordinary skill in the art to implement the embodiments. The present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein.

0062Like reference numerals refer to like elements throughout. The present specification does not describe all components in the embodiments, and common knowledge in the art or the same descriptions of the embodiments will be omitted below. The term “part” or “portion” used herein may be implemented using hardware or software, and according to embodiments, a plurality of “parts” or “portions” may be formed as a single unit or element, or one “part” or “portion” may include a plurality of units or elements. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list. Hereinafter, the operating principles and embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

0063In the present specification, an image may include a medical image obtained by a magnetic resonance imaging (MRI) apparatus, a computed tomography (CT) apparatus, an ultrasound imaging apparatus, an X-ray apparatus, or another medical imaging apparatus.

0064Furthermore, in the present specification, an “object” may be a target to be imaged and include a human, an animal, or a part of a human or animal. For example, the object may include a body part (an organ, tissue, etc.) or a phantom.

0065<figref idref="DRAWINGS">FIG. 1</figref> is an external view and block diagram of an X-ray apparatus <b>100</b> implemented as a mobile X-ray apparatus, according to an embodiment.

0066Referring to <figref idref="DRAWINGS">FIG. 1</figref>, the X-ray apparatus <b>100</b> according to the present embodiment includes an X-ray radiation device <b>110</b> for generating and emitting X-rays, an input device <b>151</b> for receiving a command from a user, a display <b>152</b> for providing information to the user, a controller <b>120</b> for controlling the X-ray apparatus <b>100</b> according to the received command, and a communication unit <b>140</b>, i.e., a communication device or interface, for communicating with an external device.

0067The X-ray radiation device <b>110</b> may include an X-ray source for generating X-rays and a collimator for adjusting a region irradiated with the X-rays generated by the X-ray source.

0068When the X-ray apparatus <b>100</b> is implemented as a mobile X-ray apparatus, a main body <b>101</b> connected to the X-ray radiation device <b>110</b> is freely movable, and an arm <b>103</b> connecting the X-ray radiation device <b>110</b> and the main body <b>101</b> to each other is also rotatable and linearly movable. Thus, the X-ray radiation device <b>110</b> may be moved freely in a three-dimensional (3D) space.

0069The input device <b>151</b> may receive commands for controlling imaging protocols, imaging conditions, imaging timing, and locations of the X-ray radiation device <b>110</b>. The input device <b>151</b> may include a keyboard, a mouse, a touch screen, a microphone, a voice recognizer, etc.

0070The display <b>152</b> may display a screen for guiding a user's input, an X-ray image, a screen for displaying a state of and the like.

0071The controller <b>120</b> may control the X-ray apparatus <b>100</b>, imaging conditions and imaging timing of the X-ray radiation device <b>110</b> according to a control command input by the user and generate a medical image based on image data received from an X-ray detector <b>200</b>. Furthermore, the controller <b>120</b> may control a position or orientation of the X-ray radiation device <b>110</b> according to imaging protocols and a position of an object.

0072The controller <b>120</b> may include a memory configured to store programs for performing the above operations of the X-ray apparatus <b>100</b> as well as operations thereof that will be described below and a processor or a microprocessor configured to execute the stored programs. The controller <b>120</b> may include a single processor or a plurality of processors or microprocessors. When the controller <b>120</b> includes the plurality of processors, the plurality of processors may be integrated onto a single chip or be physically separated from one another.

0073A holder <b>105</b> may be formed on the main body <b>101</b> so as to accommodate the X-ray detector <b>200</b>. Furthermore, a charging terminal is disposed in the holder <b>105</b> so as to charge the X-ray detector <b>200</b>. In other words, the holder <b>105</b> may be used to accommodate and also to charge the X-ray detector <b>200</b>.

0074The input device <b>151</b>, the display <b>152</b>, the controller <b>120</b>, and the communication unit <b>140</b> may be provided on the main body <b>101</b>. Image data acquired by the X-ray detector <b>200</b> may be transmitted to the main body <b>101</b> for image processing, and then the resulting image may be displayed on the display <b>152</b> or transmitted to an external device via the communication unit <b>140</b>.

0075Furthermore, the controller <b>120</b> and the communication unit <b>140</b> may be separate from the main body <b>101</b>, or only some components of the controller <b>120</b> and the communication unit <b>140</b> may be provided on the main body <b>101</b>.

0076The X-ray apparatus <b>100</b> may be connected to external devices such as an external server <b>31</b>, a medical apparatus <b>32</b>, and a portable terminal <b>33</b> (e.g., a smart phone, a tablet PC, or a wearable device) in order to transmit or receive data via the communication unit <b>140</b>.

0077The communication unit <b>140</b> may include at least one component that enables communication with an external device. For example, the communication unit <b>140</b> may include at least one of a local area communication module, a wired communication module, and a wireless communication module

0078Furthermore, the communication unit <b>140</b> may receive a control signal from an external device and transmit the received control signal to the controller <b>120</b> so that the controller <b>120</b> may control the X-ray apparatus <b>100</b> according to the received control signal.

0079Alternatively, by transmitting a control signal to an external device via the communication unit <b>140</b>, the controller <b>120</b> may control the external device according to the transmitted control signal. For example, the external device may process data according to a control signal received from the controller <b>120</b> via the communication unit <b>140</b>.

0080Furthermore, the communication unit <b>140</b> may further include an internal communication module that enables communications between components of the X-ray apparatus <b>100</b>. A program for controlling the X-ray apparatus <b>100</b> may be installed on the external device and may include instructions for performing some or all of the operations of the controller <b>120</b>.

0081The program may be preinstalled on the portable terminal <b>33</b>, or a user of the portable terminal <b>33</b> may download the program from a server providing an application for installation. The server for providing an application may include a recording medium having the program recorded thereon.

0082In addition, the main body <b>101</b> may be equipped with an alternating current (AC) power cord <b>750</b> and/or a switch <b>716</b>. The user may connect the AC power cord <b>750</b> to an outlet (not shown) when a battery management system (BMS) is shut down to wake up the BMS from shutdown. Furthermore, the user presses the switch <b>716</b> when the BMS is shut down to wake up the BMS from shutdown.

0083<figref idref="DRAWINGS">FIG. 2</figref> is an external view of the X-ray detector <b>200</b>.

0084As described above, the X-ray detector <b>200</b> used in the X-ray apparatus <b>100</b> may be implemented as a portable X-ray detector. In this case, the X-ray detector <b>200</b> may be equipped with a battery for supplying power to operate wirelessly, or as shown in <figref idref="DRAWINGS">FIG. 2</figref>, may operate by connecting a charge port <b>201</b> to a separate power supply via a cable C.

0085A case <b>203</b> maintains an external appearance of the X-ray detector <b>200</b> and has therein a plurality of detecting elements for detecting X-rays and converting the X-rays into image data, a memory for temporarily or permanently storing the image data, a communication module for receiving a control signal from the X-ray apparatus <b>100</b> or transmitting the image data to the X-ray apparatus <b>100</b>, and a battery. Furthermore, image correction information and intrinsic identification (ID) information of the X-ray detector <b>200</b> may be stored in the memory, and the stored ID information may be transmitted together with the image data during communication with the X-ray apparatus <b>100</b>.

0086<figref idref="DRAWINGS">FIG. 3</figref> is a block diagram of an X-ray apparatus <b>100</b> according to an embodiment.

0087Referring to <figref idref="DRAWINGS">FIG. 3</figref>, the X-ray apparatus <b>100</b> according to the present embodiment may include an X-ray radiation device <b>305</b>, a controller <b>310</b>, a power supply <b>320</b> including a lithium ion battery <b>322</b>, and a charger <b>330</b>. The X-ray apparatus <b>100</b> may further include a high voltage generator (not shown) provided on a main body. The X-ray apparatus <b>100</b> of <figref idref="DRAWINGS">FIG. 3</figref> may be implemented as a mobile X-ray apparatus as shown in <figref idref="DRAWINGS">FIG. 1</figref>, and <figref idref="DRAWINGS">FIG. 3</figref> illustrates only components related to the present embodiment. Thus, it will be understood by those of ordinary skill in the art that the X-ray apparatus <b>100</b> may further include common components other than those shown in <figref idref="DRAWINGS">FIG. 3</figref>.

0088The descriptions with respect to the X-ray radiation device <b>110</b> in <figref idref="DRAWINGS">FIG. 1</figref> may apply to descriptions with respect to the X-ray radiation device <b>305</b>, and thus, are not repeated. Furthermore, the descriptions with respect to the controller <b>120</b> in <figref idref="DRAWINGS">FIG. 1</figref> may apply to descriptions with respect to the controller <b>310</b>, and thus, are not repeated.

0089The power supply <b>320</b> may supply power to a load via the lithium ion battery <b>322</b>. For example, the load may include the X-ray radiation device <b>305</b>, the controller <b>310</b>, and various other components of the X-ray apparatus <b>100</b>, to which power is supplied. In other words, the lithium ion battery <b>322</b> may supply operating power to the X-ray radiation device <b>305</b> and the controller <b>310</b>.

0090Furthermore, the power supply <b>320</b> may supply, via the lithium ion battery <b>322</b>, operating power to components of the X-ray apparatus <b>100</b> that require the operating power. For example, the power supply <b>320</b> may supply operating power to the input device <b>151</b>, the display <b>152</b>, and the communication unit <b>140</b> of the X-ray apparatus <b>100</b> via the lithium ion battery <b>322</b>.

0091The power supply <b>320</b> may control overcurrent that occurs during emission of X-rays by the X-ray radiation device <b>305</b>. In other words, as the X-ray radiation device <b>305</b> emits X-rays, overcurrent that is higher than a normal operating current may flow in the power supply <b>320</b>, and the power supply <b>320</b> may control the overcurrent. According to an embodiment, in order to control overcurrent, the power supply <b>320</b> may construct a circuit consisting of a discharge field effect transistor (FET) having FETs connected in parallel and a charge FET. According to another embodiment, in order to control the overcurrent, the power supply <b>320</b> may construct a circuit including current sensors having different capacities for measuring the amount of discharge current.

0092The charger <b>330</b> may charge the power supply <b>320</b>. In detail, the charger <b>330</b> may supply a charging power to charge the lithium ion battery <b>322</b> of the power supply <b>320</b>. In this case, the charging power may be a power generated by the charger <b>330</b>. According to an embodiment, the charger <b>330</b> may be combined with an external power supply to receive power from the external power supply. The charger <b>330</b> may then control the received power according to a user input or arithmetic operations performed within the X-ray apparatus <b>100</b>, to supply a charging power to the lithium ion battery <b>322</b>.

0093The power supply <b>320</b>, the charger <b>330</b>, and the controller <b>310</b> may each include a communication interface that enables communication therebetween. For example, the power supply <b>320</b>, the charger <b>330</b>, and the controller <b>310</b> may communicate with one another via their communication interfaces according to a controller area network (CAN) protocol. Furthermore, according to another embodiment, communications may be performed among the power supply <b>320</b>, the charger <b>330</b>, and the controller <b>310</b> by using a high-speed digital interface such as low voltage differential signaling (LVDS), an asynchronous serial communication protocol such as a universal asynchronous receiver transmitter (UART), a low-latency network protocol such as an error synchronous serial communication protocol, or other various communication methods that are obvious to those of ordinary skill in the art. Furthermore, the power supply <b>320</b>, the charger <b>330</b>, and the controller <b>310</b> may each be constituted by a different module. Thus, since the controller <b>310</b> does not need to directly monitor a high voltage, a high voltage circuit is not needed within the controller <b>310</b>. This may consequently reduce the risks associated with the high voltage circuit, thereby effectively improving stability.

0094In detail, in a mobile X-ray apparatus using a conventional lead-acid battery, a controller may include a circuit for monitoring a high voltage state, and may be damaged by high voltages. On the other hand, in the X-ray apparatus <b>100</b> according to the present embodiment, a BMS of the power supply <b>320</b> may monitor a high voltage state and transmit the high voltage state to the controller <b>310</b>. This configuration may reduce the risk of damage to the controller <b>310</b>.

0095Furthermore, when the power supply <b>320</b>, the charger <b>330</b>, and the controller <b>310</b> are each composed of a different module, they may be used for different mobile X-ray apparatuses and thus share a common platform. Furthermore, by applying a shield case to each of the power supply <b>320</b>, the charger <b>330</b>, and the controller <b>310</b>, it is possible to suppress Electro Magnetic Interference (EMI)/Electro Magnetic Compatibility (EMC) noise that may occur therebetween.

0096<figref idref="DRAWINGS">FIG. 4</figref> illustrates components of a power supply <b>320</b> included in a mobile X-ray apparatus <b>100</b>, according to an embodiment.

0097Referring to <figref idref="DRAWINGS">FIG. 4</figref>, the power supply <b>320</b> may include a lithium ion battery <b>322</b>, a BMS <b>410</b>, a discharge FET <b>430</b>, and a charge FET <b>440</b>. The power supply <b>320</b> shown in <figref idref="DRAWINGS">FIG. 4</figref> includes only components related to the present embodiment. Furthermore, the power supply <b>320</b> may include a voltage sensor (not shown) for detecting a voltage and a temperature sensor (not shown) for detecting a temperature. Thus, one of ordinary skill in the art will understand that the power supply <b>320</b> may further include common components other than those shown in <figref idref="DRAWINGS">FIG. 4</figref>.

0098The lithium ion battery <b>322</b> is a type of secondary battery and consists of three components: an anode, a cathode, and an electrolyte. For example, lithium cobalt oxide (LiCoO₂) or lithium iron phosphate (LiFePO₄) may be used for the anode, and graphite may be used for the cathode. The lithium ion battery <b>322</b> may include a combination of a plurality of battery cells connected to each other. For example, the lithium ion battery <b>322</b> may include a total of 352 cells, e.g., a serial connection of 88 cells which are connected in parallel as 4 strings, e.g., 4 parallel cell groups each including 88 serially connected cells.

0099Furthermore, the lithium ion battery <b>322</b> may be suitable for use in a mobile X-ray apparatus due to its smaller size and lighter weight than conventional lead-acid batteries. For example, since a total weight of the power supply <b>330</b> including the lithium ion battery <b>322</b> and a peripheral circuit may be 33.2 kg, the total weight may be less than 35 kg, which is the maximum allowable gross weight for carrying on an aircraft. Thus, the power supply <b>320</b> may be transported by air as a single component.

0100The mobile X-ray apparatus <b>100</b> may supply power to an X-ray radiation device <b>305</b> through a battery, and may include the BMS <b>410</b> configured to operate a protection circuit by checking a voltage and a temperature of the battery.

0101The BMS <b>410</b> may detect a state of the lithium ion battery <b>322</b>, such as a voltage and a temperature thereof. According to an embodiment, the BMS <b>410</b> may include a battery stack monitor circuit designed to monitor a voltage of the lithium ion battery <b>322</b> and a temperature of a battery cell. The BMS <b>410</b> may control and manage the power supply <b>320</b> based on the state of the lithium ion battery <b>322</b>. Furthermore, the BMS <b>410</b> may control on/off states of the charge FET <b>440</b> and the discharge FET <b>430</b> to manage a charge path and a discharge path, respectively.

0102Furthermore, the BMS <b>410</b> may operate a protection circuit based on the state of the lithium ion battery <b>322</b>. In other words, the BMS <b>410</b> may operate, based on the state of the lithium ion battery <b>322</b>, the protection circuit to protect the lithium ion battery <b>322</b> from dangerous conditions. In detail, based on the state of the lithium ion battery <b>322</b>, the BMS <b>410</b> may operate the protection circuit to protect the lithium ion battery <b>322</b> against at least one of over-discharge, overcurrent, overheating, and unbalancing between battery cells.

0103The BMS <b>410</b> may operate, based on the state of the lithium ion battery <b>322</b>, the protection circuit by checking states of over-discharge, overcurrent, overheating, and unbalancing between battery cells, and may accordingly be shut down.

0104The BMS <b>410</b> may operate the protection circuit when the lithium ion battery <b>322</b> is in an over-discharged state where a voltage of the lithium ion battery <b>322</b> is lower than a reference voltage. For example, if a voltage of the lithium ion battery <b>322</b> drops to less than or equal to 275 V, the BMS <b>410</b> may operate a shutdown circuit to turn itself off. Furthermore, the BMS <b>410</b> may operate the protection circuit when the lithium ion battery <b>322</b> is in an overcurrent state where a current of the lithium ion battery <b>322</b> is higher than a reference value. For example, if the current of the lithium ion battery <b>322</b> is greater than or equal to 40 A, the BMS <b>410</b> may operate a shutdown circuit to reset itself. The BMS <b>410</b> may also operate the protection circuit when the lithium ion battery <b>322</b> is in an overheated state where a temperature of the lithium ion battery <b>322</b> is higher than a reference value. For example, if the temperature of the lithium ion battery <b>322</b> is greater than or equal to 70° C., the BMS <b>410</b> may operate the protection circuit to shut off a charge path and a discharge path. Furthermore, when the lithium ion battery <b>322</b> is unbalanced between cells, the BMS <b>410</b> may operate the protection circuit. For example, if a voltage difference between cells in the lithium ion battery <b>322</b> remains greater than or equal to 0.5 V for ten (10) seconds or more, the BMS <b>410</b> may operate a shutdown circuit to turn itself off.

0105The BMS <b>410</b> may communicate with a controller <b>310</b> via a communication interface <b>412</b>, e.g., according to a CAN protocol. Further, the charger <b>330</b> may communicate with the controller <b>310</b> via a communication interface <b>414</b>, e.g., according to the CAN protocol.

0106A load <b>406</b> may receive power via a charge path and/or a discharge path.

0107The discharge FET <b>430</b> may include a plurality of FETs <b>432</b> connected in parallel. Since overcurrent may flow in the power supply <b>320</b> during X-ray emission by the X-ray radiation device <b>305</b>, the FETs having a specific capacity in the discharge FET <b>430</b> may be connected in parallel. In other words, by connecting the FETs having the specific capacity in parallel, a maximum allowable current capacity of the discharge FET <b>430</b> may be increased. For example, if overcurrent greater than or equal to 300 A flows within the power supply <b>320</b> during X-ray emission by the X-ray radiation device <b>305</b>, the discharge FET <b>430</b> may include 4 FETs which are connected in parallel and have a capacity of 100 A each for the protection against the overcurrent.

0108According to an embodiment, the discharge FET <b>430</b> and the charge FET <b>440</b> may each be constituted by an N-channel FET.

0109The discharge FET <b>430</b> and the charge FET <b>440</b> may control a path of discharge or charge current when the lithium ion battery <b>322</b> is discharged or charged. According to an embodiment, when the lithium ion battery <b>322</b> is discharged, the charge FET <b>440</b> may be turned off, and a discharge current loop may be formed by the discharge FET <b>430</b>. According to another embodiment, when the lithium ion battery <b>322</b> is charged, the discharge FET <b>430</b> may be turned off, and a charge current loop may be formed by a diode or diodes <b>434</b> included in the discharge FET <b>430</b> and the charge FET <b>440</b>. Furthermore, the lithium ion battery <b>322</b> may be discharged and charged at the same time via the discharge FET <b>430</b> and the charge FET <b>440</b>.

0110Furthermore, while <figref idref="DRAWINGS">FIG. 4</figref> shows that a load <b>406</b> for receiving a power from the lithium ion battery <b>322</b> includes the controller <b>310</b> and the X-ray radiation device <b>305</b>, the load <b>406</b> may further include other components of the X-ray apparatus <b>100</b> that require power.

0111<figref idref="DRAWINGS">FIG. 5</figref> is a schematic diagram illustrating discharging of a lithium ion battery <b>322</b> according to an embodiment.

0112An on/off state of a discharge FET <b>430</b> may be controlled based on a signal output from a BMS <b>410</b>. In detail, the discharge FET <b>430</b> may be turned on when the lithium ion battery <b>322</b> is discharged and be turned off when the lithium ion battery <b>322</b> is charged. The signal may be coupled to a gate terminal of the discharge FET <b>430</b>. When the discharge FET <b>430</b> is turned off, a current path is formed from a minus terminal of the lithium ion battery <b>322</b> to a charger <b>330</b> via a body diode.

0113In detail, when the lithium ion battery <b>322</b> is discharged, a charge FET <b>440</b> may be turned off since a source (S) voltage of the charge FET <b>440</b> is higher than a drain (D) voltage thereof. Furthermore, when the lithium ion battery <b>322</b> is discharged, a discharge FET <b>430</b> may be turned on since a drain (D) voltage of the discharge FET <b>430</b> is higher than a source (S) voltage thereof.

0114Thus, as shown in <figref idref="DRAWINGS">FIG. 5</figref>, a discharge current loop may be formed in a clockwise direction in which a discharge current flows through a load <b>406</b>, the discharge FET <b>430</b>, and the lithium ion battery <b>322</b>. Furthermore, even when the charge FET <b>440</b> is turned off, discharging of the lithium ion battery <b>322</b> may be performed normally.

0115<figref idref="DRAWINGS">FIG. 6</figref> is a schematic diagram illustrating charging of a lithium ion battery <b>322</b> according to an embodiment.

0116An on/off state of a charge FET <b>440</b> may be controlled based on a signal output from a BMS <b>410</b>. In detail, the charge FET <b>440</b> may be turned on when the lithium ion battery <b>322</b> is charged and be turned off when the lithium ion battery <b>322</b> is discharged. When the charge FET <b>440</b> is turned off, a current path from the load <b>406</b> to a minus terminal of the lithium ion battery <b>322</b> may be formed.

0117In detail, when the lithium ion battery <b>322</b> is charged, a discharge FET <b>430</b> may be turned off since a source (S) voltage of the discharge FET <b>430</b> is higher than a drain (D) voltage thereof. When the discharge FET <b>430</b> is turned off, a charge current may flow through a body diode of the discharge FET <b>430</b>. Furthermore, when the lithium ion battery <b>322</b> is charged, the charge FET <b>440</b> may be turned on since a drain (D) voltage of the charge FET <b>440</b> is higher than a source (S) voltage thereof.

0118Thus, as shown in <figref idref="DRAWINGS">FIG. 6</figref>, a charge current loop may be formed in a counter-clockwise direction in which a charge current flows through a charger <b>330</b>, the lithium ion battery <b>322</b>, a diode <b>434</b> of the discharge FET <b>430</b>, and the charge FET <b>440</b>. Furthermore, even when the discharge FET <b>430</b> is turned off, charging of the lithium ion battery <b>322</b> may be performed normally.

0119<figref idref="DRAWINGS">FIG. 7</figref> is a detailed block diagram of a mobile X-ray apparatus <b>100</b> according to an embodiment.

0120Referring to <figref idref="DRAWINGS">FIG. 7</figref>, a power supply <b>320</b> may include a lithium ion battery <b>322</b>, a BMS <b>410</b>, a discharge FET <b>430</b>, a charge FET <b>440</b>, a shutdown circuit <b>710</b>, a first current sensor <b>730</b>, a second current sensor <b>740</b>, a DC-to-DC (DC-DC) converter <b>720</b>, and a fuse <b>760</b>. Furthermore, the X-ray apparatus <b>100</b> may include a third current sensor <b>751</b>. Since the lithium ion battery <b>322</b>, the BMS <b>410</b>, the discharge FET <b>430</b>, and the charge FET <b>440</b> respectively correspond to the lithium ion battery <b>322</b>, the BMS <b>410</b>, the discharge FET <b>430</b>, and the charge FET <b>440</b> described with reference to <figref idref="DRAWINGS">FIG. 4</figref>, detailed descriptions thereof will be omitted below. The first and second current sensors <b>730</b> and <b>740</b> may include a Hall sensor, and the shutdown circuit <b>710</b> that is a protection circuit may include a switching circuit such as a FET.

0121The BMS <b>410</b> may detect current of the lithium ion battery <b>322</b> by using different current sensors, i.e., the first and second current sensors <b>730</b> and <b>740</b>. In detail, the BMS <b>410</b> may detect current flowing in the lithium ion battery <b>322</b> by using the first current sensor <b>730</b>. The first current sensor <b>730</b> may be a small-capacity sensor for detecting a current having a relatively low intensity. In other words, the first current sensor <b>730</b> may be a sensor for detecting a current having an intensity less than or equal to a reference level. For example, the first current sensor <b>730</b> may detect a current that is less than or equal to 50 A. Furthermore, when overcurrent flows in the lithium ion battery <b>322</b>, the BMS <b>410</b> may detect overcurrent flowing in the lithium ion battery <b>322</b> by using the second current sensor <b>740</b>. The second current sensor <b>740</b> may be a large-capacity sensor for detecting a current having a relatively high intensity. In other words, the second current sensor <b>740</b> may be a sensor for detecting a current having an intensity greater than or equal to a reference level. For example, the second current sensor <b>740</b> may detect a current that is greater than or equal to 300 A.

0122According to an embodiment, the BMS <b>410</b> may detect, via the first current sensor <b>730</b>, current flowing in the lithium ion battery <b>322</b> by activating the first current sensor <b>730</b> while deactivating the second current sensor <b>740</b>. Then, when an X-ray radiation device <b>305</b> emits X-rays, the BMS <b>410</b> may detect overcurrent that occurs during the X-ray emission via the second current sensor <b>740</b> by activating the second current sensor <b>740</b> while deactivating the first current sensor <b>730</b>. Subsequently, when the X-ray emission is completed, the BMS <b>410</b> may detect, via the first current sensor <b>730</b>, current flowing in the lithium ion battery <b>322</b> by activating the first current sensor <b>730</b> while deactivating the second current sensor <b>740</b>. According to an embodiment, the BMS <b>410</b> may receive an X-ray emission preparation signal from a controller <b>310</b> and activate the second current sensor <b>740</b> to detect overcurrent occurring during X-ray emission via the second current sensor <b>740</b>.

0123The BMS <b>410</b> may check the residual amount of the lithium ion battery <b>322</b> based on the amount of current detected using the first and second current sensors <b>730</b> and <b>740</b>. In detail, the BMS <b>410</b> may use Coulomb Counting Based Gauging to check the residual amount of the lithium ion battery <b>322</b> based on the detected amount of current.

0124Furthermore, the mobile X-ray apparatus <b>100</b> may further include the third current sensor <b>751</b> for measuring a charge current. In other words, the mobile X-ray apparatus <b>100</b> may further include the third current sensor <b>751</b> at an output terminal <b>752</b> of the charger <b>330</b>. When the lithium ion battery <b>322</b> is charged and discharged at the same time, current measured by the first or second current sensor <b>730</b> or <b>740</b> may be a sum of a discharge current and a charge current. Thus, in order to accurately measure a discharge current and a charge current, the mobile X-ray apparatus <b>100</b> may measure the charge current by using the third current sensor <b>751</b>.

0125The BMS <b>410</b> may receive signals indicating that the X-ray radiation device <b>305</b> starts emission of X-rays and that the X-ray radiation device <b>305</b> completes the emission of X-rays from the controller <b>310</b> via a communication interface <b>412</b>.

0126The BMS <b>410</b> may output a first signal based on a state of the lithium ion battery <b>322</b>. The first signal may be a shutdown signal that is applied to the shutdown circuit <b>710</b>. The BMS <b>410</b> may turn itself off by using the shutdown circuit <b>710</b>. When the BMS <b>410</b> checks a state of the lithium ion battery <b>322</b> to detect hazardous conditions such as over-discharge and overcharge, the BMS <b>410</b> may turn itself off by using the shutdown circuit <b>710</b> that serves as a protection circuit. When the BMS <b>410</b> turns itself off, power being supplied to the controller <b>310</b> is also cut off, so that the controller <b>310</b> may also turn off.

0127The fuse <b>760</b> is designed to stop continuous flowing of excessive current that is greater than a nominal value in the power supply <b>320</b> and may protect a battery cell when the lithium ion battery <b>322</b> is subjected to an external short circuit.

0128The DC-DC converter <b>720</b> may convert power supplied by the lithium ion battery <b>322</b> into a DC power for driving the BMS <b>410</b>.

0129<figref idref="DRAWINGS">FIG. 8</figref> illustrates a shutdown process performed by the mobile X-ray apparatus <b>100</b> according to an embodiment. The shutdown process will now be described with reference to <figref idref="DRAWINGS">FIGS. 7 and 8</figref>.

0130Referring to <figref idref="DRAWINGS">FIGS. 7 and 8</figref>, the power supply <b>320</b>, the controller <b>310</b>, and the charger <b>330</b> may each include a communication interface and communicate with one another via their communication interfaces. For example, the power supply <b>320</b>, the controller <b>310</b>, and the charger <b>330</b> may communicate with one another according to a CAN protocol.

0131The power supply <b>320</b> may include a first temperature sensor <b>820</b>. According to an embodiment, the power supply <b>320</b> may include the first temperature sensor <b>820</b> that is dedicated for use with the BMS <b>410</b> and may be directly monitored by the BMS <b>410</b>. The BMS <b>410</b> may use the first temperature sensor <b>820</b> to monitor a temperature of the power supply <b>320</b> and determine whether the power supply <b>320</b> is overheated. For example, if the power supply <b>320</b> is overheated to a temperature higher than a specific threshold value, the BMS <b>410</b> may control the charge FET <b>440</b> that is a charge controller and the discharge FET <b>430</b> that is a discharge controller to cut off a charge path and a discharge path and control a protection circuit to turn off the BMS <b>410</b> itself.

0132Furthermore, the power supply <b>320</b> may further include a second temperature sensor <b>810</b>. According to an embodiment, the power supply <b>320</b> may include the second temperature sensor <b>810</b> that is dedicated for use with the controller <b>310</b> and may be directly monitored by the controller <b>310</b>. The second temperature sensor <b>810</b> may be provided on outside of the BMS <b>410</b>. If a communication error occurs between the controller <b>310</b> and the BMS <b>410</b>, the controller <b>310</b> may not be able to receive temperature information of the power supply <b>320</b> from the BMS <b>410</b>. In this case, the controller <b>310</b> may monitor the temperature of the power supply <b>320</b> via the second temperature sensor <b>810</b>. Thus, when a communication error occurs, the controller <b>310</b> may determine whether to turn off the power supply <b>320</b> by using the second temperature sensor <b>810</b> regardless of the state of the BMS <b>410</b>.

0133The power supply <b>320</b> and the charger <b>330</b> may respectively include interrupt pins <b>831</b> and <b>833</b> that can be directly controlled by the controller <b>310</b>. In other words, the controller <b>310</b> may respectively transmit disable signals to the power supply <b>320</b> and the charger <b>330</b> via the interrupt pins <b>831</b> and <b>833</b>, and accordingly turn off the power supply <b>320</b> and the charger <b>330</b>. Thus, when it is determined that a temperature of the power supply <b>320</b> is equal to or higher than a specific threshold value via the second temperature sensor <b>810</b>, the controller <b>310</b> may forcibly turn off the power supply <b>320</b> and the charger <b>330</b> via the interrupt pins <b>831</b> and <b>833</b>, respectively.

0134Furthermore, when the BMS <b>410</b> operates a shutdown circuit that is a protection circuit to turn itself off, a shutdown signal from the BMS <b>410</b> may be transmitted to the controller <b>310</b>. After receiving the shutdown signal, the controller <b>310</b> may monitor whether the BMS <b>410</b> is shut down for a specific amount of time. If the BMS <b>410</b> is not shut down for the specific amount of time as a result of monitoring, the controller <b>310</b> may forcibly turn off the BMS <b>410</b> via the interrupt pin <b>831</b>. For example, after the BMS <b>410</b> activates a shutdown bit, the controller <b>310</b> may monitor whether the BMS <b>410</b> is shut down for ten (10) seconds. If the BMS <b>410</b> is not shut down for 10 seconds, the controller <b>310</b> may forcibly turn off the BMS <b>410</b> via the interrupt pin <b>831</b>.

0135<figref idref="DRAWINGS">FIG. 9</figref> illustrates an X-ray apparatus according to an exemplary embodiment.

0136According to an exemplary embodiment, the charger <b>330</b> may include a wireless charging system including a transmitting module <b>920</b>, e.g., a transmitter, and a receiving module <b>910</b>, e.g., a receiver. For example, the charger <b>330</b> may be a self-inductive wireless charging system. In the charger <b>330</b>, the transmitting module <b>920</b> may convert an AC power from an external power supply into a DC power, amplify the DC power, and transmit the amplified DC power wirelessly to the receiving module <b>910</b> via a transmitting coil. The receiving module <b>910</b> may rectify the received power to charge the lithium ion battery <b>322</b>.

0137As another example, the receiving module <b>910</b> of the charger <b>330</b> may receive a power transmitted wirelessly by the transmitting module <b>920</b> installed externally to the receiving module <b>910</b> and may rectify the received power to charge the lithium ion battery <b>322</b>. Thus, an X-ray apparatus <b>100</b> including the charger <b>330</b> may be located near the transmitting module <b>920</b> and may charge the lithium ion battery <b>322</b> by using the power transmitted wirelessly by the transmitting module <b>920</b>.

0138<figref idref="DRAWINGS">FIG. 10</figref> is a timing diagram of an operation of charging a lithium ion battery <b>322</b> according to an exemplary embodiment.

0139First, during interval A, as the charger <b>330</b> performs a charging operation, a charge voltage may increase while a charge current remains constant.

0140Thereafter, during interval B, as the lithium ion battery <b>322</b> relaxes, the charge current may decrease.

0141An interval C indicates a low current state in which a charge current less than a specific threshold value remains for a specific amount of time. The charger <b>330</b> may detect the low current state, as will be described in detail below with reference to <figref idref="DRAWINGS">FIG. 11</figref>. If the low current state is detected for a specific amount of time or a specific number of times, the charger <b>330</b> may stop a charging operation. For example, if the charger <b>330</b> detects a low current state, in which the charge current is less than or equal to 0.5 A, 10 times, the charger <b>330</b> may stop a charging operation. Thus, if the lithium ion battery <b>322</b> relaxes, the charger <b>330</b> may stop the charging operation, thereby preventing unnecessary power consumption.

0142Subsequently, during interval D, when a voltage of the lithium ion battery <b>322</b> drops to a preset value, the charger <b>330</b> may restart the charging operation, and the charge current may also increase.

0143Thereafter, during interval E, which corresponds to the interval A, as the charger <b>330</b> performs the charging operation, the charge voltage may increase while the charge current remains constant.

0144<figref idref="DRAWINGS">FIG. 11</figref> is a flowchart of a method of sensing of a low current state by the charger <b>330</b>, according to an exemplary embodiment.

0145The charger <b>330</b> may detect a charge current value (operation S<b>1101</b>).

0146The charger <b>330</b> may determine whether the detected charge current value is less than an upper off-state charge current threshold (operation S<b>1103</b>). For example, the upper off-state charge current may be 0.5 A.

0147If the detected charge current value is less than the upper off-state charge current threshold in operation S<b>1103</b>, the charger <b>330</b> may increase a low current count value by 1 (operation S<b>1105</b>). In other words, if the low current count value is increased by 1 each cycle to reach a certain count value, e.g., 10, the charger <b>330</b> may determine that the current has remained low for a certain amount of time.

0148Otherwise, if the detected charge current value is not less than the upper off-state charge current threshold in operation S<b>1103</b>, the charger <b>330</b> may determine whether the detected charge current value is greater than a lower on-state charge current threshold (operation S<b>1107</b>). For example, the lower on-state charge current threshold may be 0.8 A.

0149If the detected charge current value is greater than the lower on-state charge current threshold in operation S<b>1107</b>, the charger <b>330</b> may set the low current count value to 0 (operation S<b>1109</b>).

0150Otherwise, if the detected charge current value is not greater than the lower on-state charge current threshold in operation S<b>1107</b>, the charger <b>330</b> may detect a charge current value (operation S<b>1101</b>).

0151The charger <b>330</b> may determine whether the low current count value is five 5 (operation S<b>1111</b>).

0152If the low current count value is 5 in operation S<b>1111</b>, the charger <b>330</b> may generate a signal indicating that a charging operation is to be stopped after a lapse of a certain amount of time (operation S<b>1113</b>).

0153Otherwise, if the low current count value is not 5 in operation S<b>1111</b>, the charger <b>330</b> may determine whether the low current count value is 10 (operation S<b>1115</b>).

0154If the low current count value is 10 in operation S<b>1115</b>, the charger <b>330</b> may stop the charging operation (operation S<b>1117</b>). In other words, if the low current count value is 10, the charger <b>330</b> may determine that the low current state has remained for the certain amount of time and then stop the charging operation.

0155Otherwise, if the low current count value is not 10 in operation S<b>1115</b>, the charger <b>330</b> may detect a charge current value (operation S<b>1101</b>).

0156<figref idref="DRAWINGS">FIG. 12</figref> is an external/internal perspective view of an X-ray apparatus <b>100</b> according to an embodiment.

0157Referring to <figref idref="DRAWINGS">FIG. 12</figref>, a power supply <b>320</b> and a charger <b>330</b> are arranged inside the X-ray apparatus <b>100</b>.

0158The power supply <b>320</b> weighs approximately 33.2 kg and may be arranged in a lower part of the X-ray apparatus <b>100</b>. Thus, since a center of gravity of the X-ray apparatus <b>100</b> may be located at the bottom thereof, the X-ray apparatus <b>100</b> may be moved stably.

0159The power supply <b>320</b> may be encased in a metal case and be provided as a module that is physically separated from other components.

0160An internal structure of the power supply <b>320</b> will be described in detail below with reference to <figref idref="DRAWINGS">FIGS. 20 through 25</figref>.

0161The charger <b>330</b> receives an AC power to charge a lithium ion battery within the power supply <b>320</b>. The charger <b>330</b> may be shielded by a shield case and provided as a separate module. The charger <b>330</b> may be positioned at a front surface of the power supply <b>320</b>.

0162<figref idref="DRAWINGS">FIG. 13</figref> is an external/internal perspective view of an X-ray apparatus <b>100</b> taken from a different angle, according to an embodiment.

0163Referring to <figref idref="DRAWINGS">FIG. 13</figref>, a power supply <b>320</b> and a charger <b>330</b> are arranged inside the X-ray apparatus <b>100</b>.

0164Since the power supply <b>320</b> and the charger <b>330</b> are arranged in the same manner as described with reference to <figref idref="DRAWINGS">FIG. 12</figref>, a detailed description thereof will be omitted below.

0165<figref idref="DRAWINGS">FIG. 14</figref> illustrates a state in which a power supply <b>320</b> is detached from an X-ray apparatus <b>100</b>, according to an embodiment.

0166The power supply <b>320</b> may include a handle <b>1401</b> and may be detached from a main body <b>101</b> of the X-ray apparatus <b>100</b>. A user may use the handle <b>1401</b> to separate the power supply <b>320</b> from or mount it into the main body <b>101</b> of the X-ray apparatus <b>100</b>. The power supply <b>320</b> may include two handles <b>1401</b> that allow the user to separate the power supply <b>320</b> from the main body <b>101</b> or lift and move the power supply <b>320</b>.

0167For example, the user may pull the power supply <b>320</b> along a K direction <b>1402</b> and separate it from the main body <b>101</b>.

0168<figref idref="DRAWINGS">FIG. 15</figref> is an external/internal plan view of an X-ray apparatus <b>100</b> according to an embodiment.

0169Referring to <figref idref="DRAWINGS">FIG. 15</figref>, the X-ray apparatus <b>100</b> includes wheels <b>1301</b> and <b>1403</b>, a power supply <b>320</b>, and a charger <b>330</b>.

0170The power supply <b>320</b> may be provided between the wheels <b>1301</b> and <b>1403</b>, so that a width W<b>1</b><b>1405</b> of the X-ray apparatus <b>100</b> may be decreased. Furthermore, a width W<b>2</b><b>1407</b> of the power supply <b>320</b> may be less than the width W<b>1</b><b>1405</b>.

0171<figref idref="DRAWINGS">FIG. 16</figref> is an external view of a power supply <b>320</b> according to an embodiment.

0172Referring to <figref idref="DRAWINGS">FIG. 16</figref>, the power supply <b>320</b> may include an external case <b>1600</b>, a discharging terminal <b>1601</b>, a charging terminal <b>1603</b>, a first communication connector <b>1605</b>, a second communication connector <b>1607</b>, and handles <b>1609</b> and <b>1610</b>.

0173The external case <b>1600</b> may be made of metal, and protect the power supply <b>320</b> against external shocks and function as a shield case that blocks electromagnetic waves from entering or exiting the power supply <b>320</b>.

0174The discharging terminal <b>1601</b> is connected to a cable <b>1601</b><i>a </i>to supply power output from a battery cell in the power supply <b>320</b> to an X-ray radiation device.

0175The charging terminal <b>1603</b> is connected to a charging power supply terminal (<b>1801</b> of <figref idref="DRAWINGS">FIG. 18</figref>) of a charger (<b>330</b> of <figref idref="DRAWINGS">FIG. 18</figref>) and a cable <b>1603</b><i>a </i>to receive power necessary for charging a battery.

0176The second communication connector <b>1607</b> is connected to a charger and a controller via a cable (not shown) so that the power supply <b>320</b> may perform communications with the charger and the controller. For example, the power supply <b>320</b> may communicate with the charger and the controller according to a CAN protocol via the cable connected to the second communication connector <b>1607</b>.

0177Furthermore, the user may use the second communication connector <b>1607</b> and the cable to update firmware for the power supply <b>320</b> without separating the power supply <b>320</b> from an X-ray apparatus. For example, when the power supply <b>320</b> is mounted into the X-ray apparatus, the user may transmit data necessary to update the firmware for the power supply <b>320</b> via the controller of the X-ray apparatus.

0178The power supply <b>320</b> may include the first communication connector <b>1605</b> that is, for example, a RS232C port. When the power supply <b>320</b> is separated from the X-ray apparatus, the firmware for the power supply <b>320</b> may be updated via the first communication connector <b>1605</b>.

0179Handles <b>1609</b> and <b>1610</b> may be folding handles, but are not limited thereto. Various types of handles may be used as the handles <b>1609</b> and <b>1610</b>. Examples of the handles <b>1609</b> and <b>1610</b> may include permanent magnetic handles, removable handles, handles using concave portions formed in the external case <b>1600</b>, outward-protruding handles, etc. Furthermore, while <figref idref="DRAWINGS">FIG. 16</figref> shows that the power supply <b>320</b> is equipped with the two handles <b>1609</b> and <b>1610</b>, the number of handles may vary according to embodiments.

0180<figref idref="DRAWINGS">FIG. 17</figref> is an example of a controller <b>310</b> according to an embodiment.

0181The controller <b>310</b> may be composed of a plurality of printed circuit boards (PCBs).

0182The controller <b>310</b> may include various blocks for operating an X-ray apparatus.

0183In particular, the controller <b>310</b> may include a third communication connector <b>1701</b> and a fourth communication connector <b>1703</b> for respectively performing communications with the power supply (<b>320</b> of <figref idref="DRAWINGS">FIG. 16</figref>) and the charger (<b>330</b> of <figref idref="DRAWINGS">FIG. 18</figref>).

0184The third communication connector <b>1701</b> is connected to the second communication connector (<b>1607</b> of <figref idref="DRAWINGS">FIG. 16</figref>) of the power supply <b>320</b> so that the controller <b>310</b> may communicate with the power supply <b>320</b> according to a CAN protocol.

0185The fourth communication connector <b>1703</b> is connected to a fifth communication connector (<b>1803</b> of <figref idref="DRAWINGS">FIG. 18</figref>) of the charger <b>330</b> so that the controller <b>310</b> may communicate with the charger <b>330</b> according to the CAN protocol.

0186<figref idref="DRAWINGS">FIG. 18</figref> is an external view of the charger <b>330</b> according to an embodiment.

0187Referring to <figref idref="DRAWINGS">FIG. 18</figref>, the charger <b>330</b> may include an external case <b>1800</b>, the fifth communication connector <b>1803</b>, and the charging power supply terminal <b>1801</b>.

0188The external case <b>1800</b> may be made of metal, and protect the charger <b>330</b> against external shocks and serve as a shield case that blocks electromagnetic waves from entering or exiting the charger <b>330</b>. The fifth communication connector <b>1803</b> is connected to the fourth communication connector (<b>1703</b> of <figref idref="DRAWINGS">FIG. 17</figref>) of the controller (<b>310</b> of <figref idref="DRAWINGS">FIG. 17</figref>) so that the charger <b>330</b> may communicate with the controller <b>310</b> according to a CAN protocol. Furthermore, the charger <b>330</b> may update its firmware via the fifth communication connector <b>1803</b>.

0189The charging power supply terminal <b>1801</b> may supply power to the charging terminal (<b>1603</b> of <figref idref="DRAWINGS">FIG. 16</figref>) of the power supply <b>320</b>.

0190<figref idref="DRAWINGS">FIG. 19</figref> illustrates a state in which a power supply <b>320</b>, a controller <b>310</b>, and a charger <b>330</b> are connected to one another, according to an embodiment.

0191Referring to <figref idref="DRAWINGS">FIG. 19</figref>, an X-ray apparatus may include the power supply <b>320</b>, the controller <b>310</b>, and the charger <b>330</b>.

0192A charging terminal <b>1603</b> of the power supply <b>320</b> is connected to a charging power supply terminal <b>1801</b> of the charger <b>330</b> via a cable to receive power necessary to charge a battery cell (not shown) from the charger <b>330</b>.

0193The power supply <b>320</b>, the controller <b>310</b>, and the charger <b>330</b> are electrically connected to one another via communication connectors and cables to perform communications therebetween according to a CAN protocol.

0194For example, a second communication connector <b>1607</b> may be connected to a third communication connector <b>1701</b> of the controller <b>310</b> via a cable <b>1901</b>. A fourth communication connector <b>1703</b> of the controller <b>310</b> may be connected to a fifth communication connector <b>1803</b> of the charger <b>330</b> via a cable <b>1903</b>.

0195The power supply <b>320</b>, the controller <b>310</b>, and the charger <b>330</b> may transmit or receive data by performing communications therebetween according to the CAN protocol.

0196The X-ray apparatus may use second through fifth communication connectors <b>1607</b>, <b>1710</b>, <b>1703</b>, and <b>1803</b> to update the power supply <b>320</b> and the charger <b>330</b>. When the power supply <b>320</b> and the charger <b>330</b> are updated via the second through fifth communication connectors <b>1607</b>, <b>1710</b>, <b>1703</b>, and <b>1803</b>, firmware for the power supply <b>320</b> and firmware for the charger <b>330</b> may be respectively transmitted to the power supply <b>320</b> and the charger <b>330</b> via a system board. This eliminates the need for separating the power supply <b>320</b> and the charger <b>330</b> from the X-ray apparatus.

0197According to embodiments, the power supply <b>320</b>, the controller <b>310</b>, and the charger <b>330</b> may be connected using wireless communication.

0198<figref idref="DRAWINGS">FIG. 20</figref> illustrates an internal structure of a power supply <b>320</b> according to an embodiment.

0199Referring to <figref idref="DRAWINGS">FIG. 20</figref>, the power supply <b>320</b> may include a shutdown circuit <b>2001</b>, a master BMS circuit <b>2002</b>, an FET <b>2003</b>, a wake up button <b>2004</b>, a slave BMS circuit <b>2005</b>, a fuse <b>2006</b>, and a BMS switch <b>2007</b>.

0200Since the components <b>2001</b> through <b>2006</b> perform the same functions as their counterparts described with reference to <figref idref="DRAWINGS">FIGS. 4 through 7</figref>, detailed descriptions of the functions will be omitted below.

0201A structure in which the components are arranged along an M direction <b>2010</b> will now be described.

0202The shutdown circuit <b>2001</b> may be positioned in an upper right side of the power supply <b>320</b>.

0203The master BMS circuit <b>2002</b> may be positioned in an upper middle portion of the power supply <b>320</b> and adjacent to the shutdown circuit <b>2001</b>. Since the shutdown circuit <b>2001</b> is located close to the master BMS circuit <b>2002</b>, a cable connecting the shutdown circuit <b>2001</b> to the master BMS circuit <b>2002</b> may be shortened, and accordingly radiation noise may be reduced.

0204The shutdown circuit <b>2001</b> and the master BMS circuit <b>2002</b> may be arranged parallel to a top surface (not shown) of an external case of the power supply <b>320</b>. Due to this arrangement, electromagnetic noise radiated from an integrated circuit (IC) of the master BMS circuit <b>2002</b> in a vertical direction may be shielded by the top surface of the external case.

0205The FET <b>2003</b> may be arranged on a left side of the master BMS circuit <b>2002</b>.

0206The wake up button <b>2004</b> is positioned at a front portion of the external case. The wake up button <b>2004</b> may be a switch necessary for restarting a system after a BMS is shut down.

0207The slave BMS circuit <b>2005</b> may be positioned in a lower left side of the power supply <b>320</b>. The slave BMS circuit <b>2005</b> may be arranged parallel to a front surface of the external case. A plurality of slave BMS circuits <b>2005</b> may be arranged parallel to one another. For example, the slave BMS circuit <b>2005</b> may be constituted by eight (8) boards that are arranged parallel to one another.

0208The BMS switch <b>2007</b> may supply or block power to a BMS circuit.

0209<figref idref="DRAWINGS">FIG. 21</figref> is a cross-sectional view of a power supply <b>320</b> according to an embodiment.

0210In detail, <figref idref="DRAWINGS">FIG. 21</figref> shows a cross-section of the power supply <b>320</b> taken along the M direction (<b>2010</b> of <figref idref="DRAWINGS">FIG. 20</figref>).

0211The power supply <b>320</b> may be encased in a metal case <b>2102</b>.

0212The power supply <b>320</b> may be divided into four (4) regions.

0213Battery cells <b>2106</b> may be arranged in a lower right region of the power supply <b>320</b>. A structure of the battery cells <b>2106</b> will be described in more detail below with reference to <figref idref="DRAWINGS">FIGS. 23 and 24</figref>.

0214A slave BMS circuit <b>2107</b> may be positioned in a lower left region of the power supply <b>320</b>.

0215A plurality of circuits <b>2103</b>, i.e., a master BMS circuit, a shutdown circuit, a DC-DC converter, and a protection circuit (an FET and a fuse) may be arranged in an upper right region of the power supply <b>320</b>, which is positioned above the battery cells <b>2106</b>.

0216A plurality of components <b>2101</b>, i.e., a power switch, a wake up switch, and a CAN board may be arranged in an upper left region of the power supply <b>320</b>, which is positioned above the slave BMS circuit <b>2107</b>.

0217The battery cells <b>2106</b> and the slave BMS circuit <b>2107</b> are separated by a partition wall <b>2105</b> so that a liquid leaking from the battery cells <b>2106</b> may not flow into the slave BMS circuit <b>2107</b>. The partition wall <b>2105</b> may be constituted by a frame made of an insulation material, but is not limited thereto.

0218The battery cells <b>2106</b> and the plurality of circuits <b>2103</b> are separated by a partition wall <b>2104</b> so that a liquid leaking from the battery cells <b>2106</b> may not flow into the plurality of circuits <b>2103</b>, i.e., the master BMS circuit, the shutdown circuit, the DC-DC converter, and the protection circuit (the FET and the fuse). The partition wall <b>2104</b> may be constituted by a frame made of an insulation material, but is not limited thereto.

0219<figref idref="DRAWINGS">FIG. 22</figref> is a block diagram of a configuration of a BMS circuit according to an embodiment.

0220The BMS circuit may include a slave BMS circuit <b>2201</b> and a master BMS circuit <b>2203</b>.

0221The slave BMS circuit <b>2201</b> may manage voltages, temperatures, and unbalancing between cells of a battery pack with a number of cell groups, e.g., eleven cell groups, connected in series.

0222For cell balancing, a resistor is used to discharge overcharged cells while charging other cells.

0223As described above with reference to <figref idref="DRAWINGS">FIG. 4</figref>, four (4) individual battery cells are connected in parallel to form a cell group, and eleven cell groups are connected together in series to form a battery pack.

0224According to the embodiment, the BMS circuit includes eight (8) slave BMS circuits <b>2201</b>, but the number of slave BMS circuits <b>2201</b> may vary depending on the number of battery packs.

0225The slave BMS circuit <b>2201</b> may include a communication interface and communicate with the master BMS circuit <b>2203</b> via the communication interface to transmit voltages, temperatures, and information about unbalancing between cells of a battery pack to the master BMS circuit <b>2203</b>.

0226The master BMS circuit <b>2203</b> may collect information received from the eight slave BMS circuits <b>2201</b> to operate a protection circuit (not shown) and transmit the collected information to a system board via the communication interface (communication connector).

0227As described above, the slave BMS circuit <b>2201</b> manages a voltage and a temperature of battery cells and information about unbalancing between battery cells in a dispersed manner, and the master BMS circuit <b>2203</b> collects and manages them in an integrated manner. Due to this configuration, a size of the master BMS circuit <b>2203</b> may be reduced. In particular, by dispersedly connecting cables respectively coupled to battery cells to the slave BMS circuit <b>2201</b>, it is possible to facilitate arrangement of cables and accordingly, improve assembly capabilities. Furthermore, if a problem occurs in the slave BMS circuit <b>2201</b>, only the faulty slave BMS circuit <b>2201</b> may be replaced. Thus, service efficiency may be enhanced.

0228<figref idref="DRAWINGS">FIG. 23</figref> shows a state in which battery packs are mounted in a power supply <b>320</b> according to an embodiment.

0229Referring to <figref idref="DRAWINGS">FIG. 23</figref>, upper and lower battery packs <b>2331</b> and <b>2333</b> are mounted in an external case <b>2300</b> of the power supply <b>320</b>.

0230A reinforcement member <b>2301</b> is provided on one side of the external case <b>2300</b>.

0231The upper and lower battery packs <b>2331</b> and <b>2333</b> may be installed in the external case <b>2300</b> and stacked in two layers. A plurality of cables <b>2335</b> may be connected to the upper and lower battery packs <b>2331</b> and <b>2333</b> in order to connect the upper and lower battery packs <b>2331</b> and <b>2333</b> with slave BMS circuits (not shown).

0232A partition wall <b>2315</b> may be installed between the lower battery pack <b>2333</b> and a bottom surface of the external case <b>2300</b>.

0233A partition wall <b>2313</b> may be provided between the upper and lower battery packs <b>2331</b> and <b>2333</b>.

0234A partition wall <b>2311</b> may be provided between the upper battery pack <b>2331</b> and a region where a master BMS circuit (not shown) is positioned.

0235The partition walls <b>2311</b> and <b>2313</b> may be each formed of an insulation material.

0236Furthermore, reinforcement members <b>2321</b> and <b>2323</b> may respectively be provided on right and left sides of the upper and lower battery packs <b>2331</b> and <b>2333</b>. The reinforcement members <b>2321</b> and <b>2323</b> may protect the upper and lower battery packs <b>2331</b> and <b>2333</b> by preventing deformation of the external case <b>2300</b> caused by an external force.

0237The external case <b>2300</b> may be formed of a thick metal (e.g., with a 1.6t thickness) in order to protect the upper and lower battery packs <b>2331</b> and <b>2333</b> and other main components of the power supply <b>320</b> against an external force.

0238In addition, for battery cells in a battery pack, lithium ion battery cells are used. Since a battery pack using lithium ion batteries is relatively small and lightweight compared to a battery pack using lead-acid batteries, a slim X-ray apparatus may be provided.

0239Due to the use of a lithium ion battery, a total weight of the power supply <b>320</b> including battery cells and peripheral circuits does not exceed 35 kg, which is the maximum allowable gross weight for carrying on an aircraft. Thus, the power supply <b>320</b> may be transported by air as a single component.

0240<figref idref="DRAWINGS">FIG. 24</figref> illustrates a structure of a battery pack <b>2331</b> according to an embodiment.

0241Referring to <figref idref="DRAWINGS">FIG. 24</figref>, the battery pack <b>2331</b> may include a cell group <b>2401</b> and a battery holder <b>2402</b>.

0242The cell group <b>2401</b> includes four battery cells connected in parallel. In other words, the four battery cells are connected together to form the cell group <b>2401</b>. Furthermore, eleven cell groups are connected together in series to form the battery pack <b>2331</b>.

0243The number of battery cells in a cell group and the number of cell groups in a battery pack are merely an example, and may be adjusted to suit an intended purpose.

0244The battery holder <b>2402</b> may accommodate and protect battery cells. The battery holder <b>2402</b> may be made of a flame retardant resin and has holes <b>2403</b> formed therein for receiving the battery cells. The battery holder <b>2402</b> may also be combined with another battery holder by a pin. Since the battery cells are housed in the battery holder <b>2402</b>, even when a battery cell gets swollen, the swollen battery cell may not adversely affect another battery cell or component.

0245<figref idref="DRAWINGS">FIG. 25</figref> illustrates a configuration of a slave BMS circuit <b>2500</b> according to an embodiment.

0246Referring to <figref idref="DRAWINGS">FIG. 25</figref>, the slave BMS circuit <b>2500</b> may include a temperature sensor <b>2503</b> and a multi-cell battery stack monitor IC <b>2505</b>.

0247The temperature sensor <b>2503</b> may detect temperatures of a battery cell having eleven cell groups connected in series. In detail, the temperature sensor <b>2503</b> may be connected to a top and a bottom of four battery cells <b>2501</b> in each cell group to detect a temperature of the battery cells in each cell group.

0248The temperature sensor <b>2503</b> detects temperatures of the 11 cell groups and transmits the result to the multi-cell battery stack monitor IC <b>2505</b>.

0249As described above, a BMS circuit includes eight slave BMS circuits <b>2500</b>, each of which may transmit temperatures, voltages, and information about unbalancing between cells of a battery pack to a master BMS circuit via a communication interface.

0250<figref idref="DRAWINGS">FIG. 26</figref> illustrates a structure in which a system board <b>2603</b> is mounted on a side of an X-ray apparatus, according to an embodiment.

0251Referring to <figref idref="DRAWINGS">FIG. 26</figref>, frames <b>2601</b> and <b>2605</b> and the system board <b>2603</b> are provided on a side of the X-ray apparatus.

0252The system board <b>2603</b> may be a part of a controller.

0253The frames <b>2601</b> and <b>2605</b> may each have one side attached to a main body <b>101</b> via a hinge and may be pivoted around a hinge axis.

0254As the frames <b>2601</b> and <b>2605</b> are pivoted around the hinge axis, an internal system board mounted in the frames <b>2601</b> and <b>2605</b> may be exposed to outside the frames <b>2601</b> and <b>2605</b>.

0255Circuit components <b>2606</b>, <b>2607</b>, <b>2608</b>, and <b>2609</b> and the system board <b>2603</b> may be mounted on the frames <b>2601</b> and <b>2605</b>.

0256<figref idref="DRAWINGS">FIG. 27</figref> illustrates a state in which the frames <b>2601</b> and <b>2605</b> of <figref idref="DRAWINGS">FIG. 26</figref> are open.

0257<figref idref="DRAWINGS">FIG. 27</figref> shows the frames <b>2601</b> and <b>2605</b> and an internal system board <b>2701</b>.

0258The frames <b>2601</b> and <b>2605</b> may be pivoted around a hinge axis to be opened or closed in a transverse direction.

0259When the frames <b>2601</b> and <b>2605</b> open, the internal system board <b>2701</b> may be exposed to outside. When a problem occurs in the internal system board <b>2701</b>, the internal system board <b>2701</b> may be easily detached from the main body <b>101</b> by opening the frames <b>2601</b> and <b>2605</b> in the transverse direction. Accordingly, service efficiency may be increased.

0260While one or more embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the following claims. Accordingly, the above embodiments and all aspects thereof are examples only and are not limiting.